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@rsofaer @kaplanoah this is ready for merge. Please review at your leisure and comment/ask questions as necessary.

New/fixed functionality in this pull:

* Fixed: 
Authentication with github and redirecting to /students
  Currently *not* storing an authentication token for a given user
  We are currently implementing this: http://octokit.github.io/octokit.rb/#Application_authentication
Routes are now less complicated, with submissions route being a nested route within students
  Currently *not* actually associating submissions with students

* New: 
Specs for most existing user-facing functionality, including omniauth_callbacks_controller
Using Octokit for interfacing with github api
Octokit wrapper as a singleton with environment-based config of authentication token for app
 for making Octokit available throughout the app
RSpec helper module for mocking Octokit functionality
RSpec helper module for mocking various omniauth-related functionality
Pull requests now being displayed for all repos in wdi-sf-jan-2014 organization
ERB replaced with HAML
Overall code clean up